package com.atguigu.flinkState;

import com.atguigu.been.WaterSensor;
import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.api.common.functions.ReduceFunction;
import org.apache.flink.api.common.state.ReducingState;
import org.apache.flink.api.common.state.ReducingStateDescriptor;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.KeyedProcessFunction;
import org.apache.flink.util.Collector;

/**
 * @author wky
 * @create 2021-07-19-9:35
 */
// ReducingState	输入输出类型相同  计算每个传感器的水位和
public class State_Keyed_Reducing {
    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment senv = StreamExecutionEnvironment.getExecutionEnvironment();

        senv.setParallelism(1);
        DataStreamSource<String> source = senv.socketTextStream("hadoop102", 9999);
        SingleOutputStreamOperator<WaterSensor> map = source.map(new MapFunction<String, WaterSensor>() {
            @Override
            public WaterSensor map(String value) throws Exception {
                String[] split = value.split(",");
                return new WaterSensor(split[0], Long.parseLong(split[1]), Integer.parseInt(split[2]));
            }
        });
        KeyedStream<WaterSensor, String> keyedStream = map.keyBy(WaterSensor::getId);
        //计算每个传感器的水位和
        keyedStream.process(new KeyedProcessFunction<String, WaterSensor, String>() {
            //设置状态值
            private ReducingState<Integer> reducingState;

            @Override
            public void open(Configuration parameters) throws Exception {
                //初始化  写入集合逻辑 防止空指针异常 加载时间的问题
                reducingState=getRuntimeContext().getReducingState(new ReducingStateDescriptor<Integer>("reduce", new ReduceFunction<Integer>() {
                    @Override
                    public Integer reduce(Integer value1, Integer value2) throws Exception {
                        return value1+value2 ;
                    }
                }, Integer.class));
            }

            @Override
            public void processElement(WaterSensor value, Context ctx, Collector<String> out) throws Exception {
               reducingState.add(value.getVc());
               out.collect(ctx.getCurrentKey()+"--"+reducingState.get());

            }
        }).print();
        senv.execute();


    }
}
